Exhaust heater-muffler combination



July 10, 1962 s. J. HANNON EXHAUST HEATER-MUFFLER COMBINATION 2 Sheets-Sheet 1 Filed Oct. 1'7 1961 INVENTOR. .Sfephen J. Hannon MM,

BY HIS ATTORNE Y5 July 10, 1962 5. J. HANNON 3,043,098

EXHAUST HEATER-MUFFLER COMBINATION Filed Oct. 17, 1961 2 Sheets-Sheet 2 INVENTOR. Stephen J. Hannon BY Main r- 50M HIS A TTOR/VE Y5 United States Patent 3,043,098 Patented July 10, 1962 3,043,098 EXHAUST HEATER-MUFFLER COMBINATION Stephen J. Harmon, Pittsburgh, Pa., assignor t Hanlon & Wilson Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed Oct. 17, 1961, Ser. No. 145,656 8 Claims. (Cl. 60--31) This invention relates to exhaust gas apparatus and to mufflers and exhaust gas heater-muffler combinations. It particularly pertains to exhaust gas apparatus and exhaust heater-mufiler combinations for 4-cylinder and 6- cylinder, horizontal opposed engines for aircraft.

Heretofore, application of exhaust gas apparatus, including mufilers and heater-muffler combinations to internal combustion engines, especially the 4- and 6-cylinder, horizontal opposed type engines, caused substantial amounts of loss in horsepower of those engines during their operation. Those losses in horsepower resulted from high back pressures of the exhaust gases in conduits which conveyed the gases from the individual cylinders of the engine and/ or in the mufflers or exhaust gas apparatus connected to the conduits. Not only did horsepower losses occur, but also a shorter engine life due to surges of back pressure which tended to drive the exhaust gases back into the cylinders of the engines.

My invention provides exhaust gas apparatus such as amuffier and a heater-mufiler combination which generates little or no back pressure and thereby avoids losses in useful horsepower of the engine and also a shortened engine life. Specifically, my exhaust gas apparatus cornprises a duct member closed at each end to form an en closed space-for receiving exhaust gases therein. Within the duct is a partition member which divides the duct into a first chamberand a second chamber. Extending through the duct member is a first exhaust gas conduit having an opening into the first chamber. Likewise, a second exhaust gas conduit extends through the duct member andhas an opening into the second chamber.

a The first and second exhaust gas conduits are adapted to be connected to flows of exhaust gases from individual cylinders of an internal combustion engine so that they alternately deliver into their respective chambers a flow ofexhaust gas from a cylinder of the engine. Then, a tail pipe which has an opening into each of the two chambers and extends through the duct member conveys the exhaust gases from the apparatus.

My invention as applied to an exhaust heater-muffler combination'adds to the foregoing exhaust gas apparatus, a shroud which surrounds the duct member and is spaced apart from its outside walls to form an air warming enclosure defined by't he outside walls of the duct member and the inside walls of the shroud. Connected into the enclosure is an inlet duct for delivering air to be warmed thereto. An outlet duct spaced apart from the inlet duct and also connected into the air warming enclosure conveys warmed air from the combination.

In the accompanying drawings I have shown a preferred embodiment of my invention in which:

FIGURE 1 is a side elevation view of my invention applied to an exhaust gas heater-mufiier combination;

FIGURE 2 is a section view along the line II-II of FIGURE 1;

FIGURE 3 is a section view along the line III-III of FIGURE 2; 7

FIGURE 4 is a section viewalong the line IVIV of FIGURE 2; and

FIGURE 5 is a section view along the line V-V of FIGURE 4.

As shown in FIGURES 15 inclusive, my exhaust gas distance from heater-mufiier combination comprises a substantially cylindrical shroud 1 which has end rings 2 and 3 at its ends. Disposed within the shroud and spaced apart from its inside walls 1a by the two end rings is a core member 4 which extends longitudinally of the shroud and is made from two half shell sections. At the ends of the core member are header plates 5 and 6 for forming with the core member an enclosed space 7 Within the shroud for receiving exhaust gases from a 4-cylinder, horizontal opposed aircraft engine (not shown).

The inside walls 1a of the shroud 1, the end rings 2 and 3, and the outside walls 4a of the core member 4 define an air warming enclosure 8. Extending through the shroud 1 and opening into the air Warming enclosure 8 is an inlet duct 9 which delivers air to be warmed thereto. Air which has been warmed within the enclosure as will be described hereinafter is conveyed therefrom to an aircraft cabin (not shown) or other device requiring warmed air by an outlet duct it) also extending through the shroud and opening into the enclosure. As shown, the inlet duct 9 is spaced apart from the outlet duct 10. v

In the event warmed air is desired for a carburetor of the aircraft engine, a second outlet duct 11 is provided and, like the first-described one, extends through the shroud and opens into the enclosure 8.

To insure that the air to be warmed does not travel directly from the inlet duct 9 around the core member 4 to the outlet duct 10 and thereby avoid adequate warming, two baffle plates 12 and 13 in the shape of angle sections are interposed between the inlet and outlet ducts and located about apart as shown in FIGURE 2. The two bafiie plates extend from end ring 2 substantially the length of the core member 4 and terminate a short the other end ring 3 to provide an inlet part 14 and an outlet part 15 of the enclosure 8 and an interconnection .16 between the two parts. Since each bafile plate extends from the outside wall 4a of the core member to the inside wall 111 of the shroud for their length, air which enters the enclosure through the inlet duct must travel the length of the inlet part 14 before passing over to the outlet part 15 as shown by arrows 17 and then to the outlet duct. In this way, the entering air is adequately warmed before it exits from the enclosure.

As shown in FIGURES 2 and 3, a partition sheet 18 disposed within the core member 4 divides it into a first chamber 19 and a second chamber 20 each designed for receiving exhaust gases delivered thereto.

Extending through header plate 5 and into the first chamber 19 is a first exhaust gas conduit 21 which receives and conveys an exhaust gas flow from #1 cylinder (not shown) of the 4-cylinder, horizontal opposed aircraft engine (not shown). This first exhaust gas conduit has a portion 22 inside the first chamber 19 and an end cap 23 at its terminal, as shown in FIGURE 3. To provide muffiing characteristics to the combination, there is a plurality of orifices 24 extending through the walls of portion 22 and through the end cap 23.

In like manner, a second exhaust gas conduit 25 which receives and conveys an exhaust gas flow from #2 cylinder of the 4-cylinder engine extends through header plate 6 and into the first chamber 19. Since this second exhaust gas conduit is substantially the same as the first one, it need not be further described. As shown, the first and second exhaust gas conduits 21 and 25 are in opposed relationship to one another (FIGURE 1); however, such a relationship is not essential and the connection of the two conduits into the first chamber 19 may have other convenient arrangements.

Extending through header plate 5 and into the second chamber 20 is a third exhaust gas conduit 26 which receives and conveys an exhaust gas fiow from #3 cylinder of the 4-cylinder engine into the second chamber. As shown, a fourth exhaust gas conduit 27 similar to the three previously described ones extends through header plate 6 and into the second chamber to deliver an exhaust gas flow from #4 cylinder of the 4-cylinder engine into the second chamber 20. Because the third and fourth conduits are similar to the first two, they will not be further described.

To enhance heat exchange between the exhaust gases and the air to be warmed, I provide heat radiating pins 28 mounted upon the core, extending on both sides thereof and running therearound. For maximum heat exchange, additional pins 29 are provided on the outside walls of the core member along those areas opposite those portions of the four exhaust gas conduits which are inside the chambers of the core member.

A tail pipe 30 extends through the shroud, through the enclosure and through the core member and has an opening 31 into each of the first and second chambers as shown in FIGURE 2 for removal of exhaust gases therefrom.

The firing order of the four cylinders of the engine is: first, cylinder #1; second, cylinder #3; third, cylinder #2; and fourth, cylinder #4. Accordingly, into the first chamer and into the second chamber there is an alternate delivery of a fiow of exhaust gas from the cylinders of the engine. For example, conduit 21 delivers a fiow of exhaust gas from cylinder #1 after firing thereof into the first chamber 19. Next, conduit 26 delivers a fiow of exhaust gas from cylinder #3 after firing thereof into the second chamber 20. The next flow of exhaust gas is from cylinder #2 and it is delivered into the first chamber 19 by conduit 25. Then, conduit 27 delivers a fiow of exhaust gas into the second chamber Ztl from cylinder #4 after its firing so that into each of the two chambers there are deliveries of alternate fiows of exhaust gases.

Since the tail pipe has an opening into both the first and second chambers, each fiow of exhaust gas travels from its respective chamber therethrough to atmosphere. This travel of first one fiow of gas from one chamber out through the tail pipe and then travel of a second flow of exhaust gas from the other chamber out through the tail pipe, etc., produces an aspirating action upon each of the four cylinders of the engine. Specifically, travel of the gas flow from cylinder #1 out through the tail pipe effects a suction upon exhaust gases from cylinder #3, the next one in firing order, and draws the exhaust gases from cylinder #3 into chamber 20. Then, escape of the fiow of exhaust gases from cylinder #3 out of chamber 2'!) and the tail pipe produces a similar suction upon cylinder #2, the next firing one. Likewise, travel of the exhaust gases from cylinder #2 out through the tail pipe effects a similar action upon cylinder #4, etc. In this way, travel of a flow of gas from one cylinder out of one chamber through the tail pipe materially helps and assists removal of exhaust gases from the next firing cylinder to eliminate, if not reduce to an extremely low level back pressure upon each of the cylinders of the 4-cylinder engine.

Tests have been conducted upon the apparatus of FIG- URES 1-5 inclusive and establish that there is little if any horsepower loss due to back pressure when my combination is applied to a 4-cylinder, horizontal opposed engine.

In the event that the exhaust gas heater part of the combination is not needed, then the shroud, end rings, air inlet, air outlets and pins can be eliminated to provide a muffler. Additionally, if the muffier feature is not desired, then the orifices in the portions of the four exhaust gas conduits need not be used and the exhaust gases then flow directly from the ends of the conduits into the respective chambers.

While the combination as shown is adapted for a 4-cylinder engine, it can also be modified easily for a 6-cylinder engine by use of additional conduits connected to cylinders #5 and #6 of a 6-cylinder engine and arranged to deliver the gas flows from those two additional cylinders 6. into the respective chambers as taught herein to provide the aspirating action.

My invention has important advantages in that it reduces back pressure upon the cylinders of an internal combustion engine so that there is little if any horsepower loss and so that engine life is not shortened due to surges of exhaust gases back into the cylinders.

While I have shown and described preferred embodiments of my invention, it may be otherwise embodied within the scope of the following claims.

I claim:

1. An exhaust heater-muffler combination comprising a shroud, a core member disposed within the shroud and spaced apart from its inside walls to form an air warming enclosure defined by outside walls of said core member and said inside walls of said shroud, an air inlet duct connected into said air warming enclosure for delivering air to be warmed thereto, an air outlet duct spaced apart from said inlet duct and connected into said air warming enclosure for conveying warmed air from said combination, a partition member disposed within said core member and dividing it into a first chamber and a second chamber, a first exhaust gas conduit means extending through said shroud and having an opening into said first chamber, a second exhaust gas conduit means extending through said shroud and having an opening into said second chamber, said first and second exhaust gas conduit means being adapted to be connected to flows of exhaust gases from individual cylinders of an internal combustion engine so that said first and second exhaust gas conduit means alternately deliver into ther respective chambers a flow of exhaust gas from a cylinder of said engine and a gas removal duct having an opening into each of said first and second chambers and extending through said shroud to convey said exhaust gas in said first and second chambers from said combination.

2. The combination of claim 1 characterized by baffle means disposed in said air warming enclosure and interposed between said connection of said inlet duct into said enclosure and said connection of said outlet duct into said enclosure.

3. The combination of claim 2 characterized by said bafile means extending longitudinally of said core member to provide an inlet part and an outlet part of said air warming enclosure and by said baffle means terminating short of one end of said core member to provide an interconnection between said inlet part and said outlet part.

4. An exhaust heater-mufiler combination comprising a shroud, a core member disposed within the shroud and spaced apart from its inside walls to form an air warming enclosure defined by outside walls of said core memher and said inside walls of said shroud, an air inlet duct connected into said air warming enclosure for delivering air to be warmed thereto, an air outlet duct spaced apart from said inlet duct and connected into said air warming enclosure for conveying warmed air from said combination, a partition member disposed within said core member and dividing it into a first chamber and a second chamber, first and second exhaust gas conduits extending through said shroud and each having an opening into said first chamber, third and fourth exhaust gas conduits extending through said shroud and each having an opening into said second chamber, said first, second, third and fourth exhaust gas conduits being adapted to be connected to flows of exhaust gases from individual cylinders of an internal combustion engine so that one of said first and second conduits and one of said third and fourth conduits alternately deliver into their respective chambers a flow of exhaust gas from a cylinder of said engine and a gas removal duct having an opening into each of said first and second chambers and extending through said shroud to convey said exhaust gas in said first and second chambers from said combination.

5. The combination of claim 4 characterized by bafile means disposed in said air warming enclosure and interposed between said connection of said inlet duct into said enclosure and said connection of said outlet duct into said enclosure.

6. The combination of claim 5 characterized by said bafiie means extending longitudinally of said core member to provide an inlet part and an outlet part in said air Warming enclosure and by said 'batfle means terminating short of one end of said core member to provide an interconnection between said inlet part and said outlet part.

7. In an exhaust heater-muflier combination having a shroud, a core member disposed within the shroud and spaced apart from its inside walls to form an air warming enclosure defined by outside walls of said core member and said inside walls of said shroud, an air inlet duct connected into said air Warming enclosure for delivering air to be warmed thereto, an outlet duct spaced apart from said inlet duct and connected into said air warming enclosure for conveying Warm from said combination, the invention comprising a partition member disposed Within said core member and dividing it into a first chamber and a second chamber, a first exhaust gas conduit means extending through said shroud and having an opening into said first chamber, a second exhaust gas conduit means extending through said shroud and having an opening into said second chamber, said first and sec- 0nd exhaust gas conduit means being adapted to be connected to flows of exhaust gases from individual cylinders of an internal combustion engine so that said first and second exhaust gas conduit means alternately deliver into their respective chambers a flow of exhaust gas from a cylinder of said engine and a gas removal duct having an opening into each of said first and second chambers and extending through said shroud to convey said exhaust gas in said first and second chambers from said combination.

8. Exhaust gas apparatus comprising a duct member closed at each end to form an enclosed space for receiv ing exhaust gas therein, a partition member disposed within said duct member and dividing it into a first chamher and a second chamber, a first exhaust gasconduit means extending through said duct member and having an opening into said first chamber, a second exhaust gas conduit means extending through said duct member and having an opening into said second chamber, said first and second exhaust gas conduit means being adapted to be connected to flows of exhaust gases from individual cylinders of an internal combustion engine so that said first and second exhaust gas conduit means alternately deliver into their respective chambers a flow of exhaust gas from a cylinder of said engine, and a gas removal tube having an opening into each of said first and second chambers and extending through said duct member to convey said exhaust gas in said first and second chambers from said apparatus.

No references cited. 

